. >> how they can justify raising taxes on the middle class that's been buried the last four years. >> reporter: paul ryan pounced. >> vice president biden, just today, said that the middle class over the last four years has been, quote, buried. we agree. that means we need to stop digging by electing mitt romney as the next president of the united states. [ applause ] >> reporter: the vice president later said that the middle class pain was due to bush policies. that romney and ryan want to repeat. the debate symbolizes a problem for the president. even though the economic collapse happened under bush, four years later, families are still hurting. many in the middle class are barely treading water. all guaranteed fodder for tomorrow night's debate in denver. the first lady is making her way there. first stop in ohio. >> are you fired up? >> reporter: where early voting began today. >> are we going sit back and watch everything we worked for and fought for to just slip away? >> reporter: ann romney got to colorado before her. >> we have a debate coming up. we're excited about that. we